A valve structure is applied, for example, to a piston portion of a damper for a vehicle, and the like.
As shown in FIG. 10, JP2006-194335A discloses a valve structure including a piston P slidably inserted into a cylinder C of a damper and partitioning an interior of the cylinder C into an extension side chamber ER and a pressure side chamber CR, pluralities of extension side ports EP and pressure side ports CP provided in the piston P and communicating between the extension side chamber ER and the pressure side chamber CR, an annular extension side leaf valve EL laminated in a pressure side chamber end of the piston P and opening and closing only the extension side ports EP, and an annular pressure side leaf valve CL laminated in an extension side chamber end of the piston P and opening and closing only the pressure side ports CP, wherein the extension side ports EP and the pressure side ports CP are alternately arranged along the circumferential direction of the piston P.